{"title":"Experimental investigation of an electromagnetic seismic isolation system with different configurations of inertance","authors":"","doi":"10.1016/j.jsv.2024.118698","DOIUrl":null,"url":null,"abstract":"<div><p>Protecting seismic isolated equipment or buildings in a near-fault area is challenging because of the strong long-period velocity components of near-fault ground motions. These long-period pulses can cause excessive base displacement of conventional seismic isolation systems. In this study, an electromagnetic seismic isolation system with flywheels (EMSIS-FW) was experimentally investigated to reduce the base displacement of isolation systems during near-fault earthquakes. The EMSIS-FW consists of a sliding platform and rotary electromagnetic (EM) dampers, which can provide an EM damping force. With an additional flywheel installed on each EM damper, its moment of inertia can offer a considerable inertance for the EMSIS-FW. The inertance generated by the flywheel can be hundreds of times larger than its mass. Accordingly, the isolation frequency can be adjusted using different-sized flywheels. A prototype EMSIS-FW was designed and manufactured. A theoretical model was also developed to predict its dynamic behavior. Through shaking table tests, this study provided experimental verification of the effectiveness of inertance on isolation systems subjected to near-fault ground motions. The experimental results indicate that an increase in inertance reduces the isolation displacement, but it may increase the isolation acceleration during a typical far-field ground motion. In addition, the accuracy of the theoretical model was verified using the shaking table test.</p></div>","PeriodicalId":17233,"journal":{"name":"Journal of Sound and Vibration","volume":null,"pages":null},"PeriodicalIF":4.3000,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Sound and Vibration","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022460X24004607","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ACOUSTICS","Score":null,"Total":0}
引用次数: 0
Abstract
Protecting seismic isolated equipment or buildings in a near-fault area is challenging because of the strong long-period velocity components of near-fault ground motions. These long-period pulses can cause excessive base displacement of conventional seismic isolation systems. In this study, an electromagnetic seismic isolation system with flywheels (EMSIS-FW) was experimentally investigated to reduce the base displacement of isolation systems during near-fault earthquakes. The EMSIS-FW consists of a sliding platform and rotary electromagnetic (EM) dampers, which can provide an EM damping force. With an additional flywheel installed on each EM damper, its moment of inertia can offer a considerable inertance for the EMSIS-FW. The inertance generated by the flywheel can be hundreds of times larger than its mass. Accordingly, the isolation frequency can be adjusted using different-sized flywheels. A prototype EMSIS-FW was designed and manufactured. A theoretical model was also developed to predict its dynamic behavior. Through shaking table tests, this study provided experimental verification of the effectiveness of inertance on isolation systems subjected to near-fault ground motions. The experimental results indicate that an increase in inertance reduces the isolation displacement, but it may increase the isolation acceleration during a typical far-field ground motion. In addition, the accuracy of the theoretical model was verified using the shaking table test.
期刊介绍:
The Journal of Sound and Vibration (JSV) is an independent journal devoted to the prompt publication of original papers, both theoretical and experimental, that provide new information on any aspect of sound or vibration. There is an emphasis on fundamental work that has potential for practical application.
JSV was founded and operates on the premise that the subject of sound and vibration requires a journal that publishes papers of a high technical standard across the various subdisciplines, thus facilitating awareness of techniques and discoveries in one area that may be applicable in others.